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Desalination and Seawater Supplies Project,Burrup Peninsula

Water Corporation

Report and Recommendationsof the Environmental Protection Authority

Environmental Protection AuthorityPerth, Western Australia

Bulletin 1014May, 2001

ISBN. 0 7307 6637 3

ISSN. 1030 – 0120

Assessment No. 1378

ContentsPage

1 . Introduction 1

2 . The proposal 1

3 . Consultation 6

4 . Relevant Environmental Factors 7

5 . Conclusions 12

6. Recommendations 12

Tables1. Summary of key proposal characteristics 52. Identified stakeholders 6

Figures

1. Location of proposal 22. Pipeline route 33. Desalination Plant General Arrangement 4

Appendices1. References2. Recommended Environmental Conditions and Proponent’s Consolidated Commitments

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1. IntroductionThis report provides the advice and recommendations of the Environmental Protection Authority(EPA) to the Minister for the Environment and Heritage on the environmental factors relevant toa proposal by the Water Corporation to construct and operate a seawater supply and desalinationsystem on the Burrup Peninsula.

The EPA was advised of the proposal in November 2000. Based on the information provided,the EPA considered that while the proposal had the potential to have an effect on theenvironment, the proposal could be readily managed to meet the EPA’s environmentalobjectives. Consequently, it was notified in The West Australian newspaper on 11 December2000 that, subject to the preparation of a suitable Environmental Protection Statement (EPS)document, the EPA intended to set the level of assessment at Proponent-initiated EnvironmentalProtection Statement.

The proponent has prepared an EPS document that accompanies this report and describes theproject, its environmental impacts and the proposed approach to their management in greaterdetail. This document is available through the Department of Environmental Protection (DEP)library in Perth and the regional office in Karratha. The EPA considers that the proposaldescribed can be managed in an acceptable manner subject to the commitments to the proposalbeing legally binding.

The EPA has determined under Section 40 (1) of the Environmental Protection Act 1986 that thelevel of assessment for the proposal be Proponent-initiated Environmental Protection Statement,and this report provides the EPA advice and recommendations in accordance with Section 44(1).

Any person who disagrees with the EPA’s decision on the level of assessment may lodge anappeal with the Minister for the Environment within 14 days of the date of the decision beingplaced in the public record.

A separate right of appeal exists for any person who disagrees with the content of, or anyrecommendations in this report, also within 14 days of release of the report.

2. The proposalThe proposal is described in detail in Section 3 of the proponent’s “Burrup PeninsulaDesalinated Water and Seawater Supplies Project” EPS document (Burns and Roe Worley,April 2001). The proposal involves the construction and operation of a seawater supply anddesalination system on the Burrup Peninsula (Figures 1 and 2) to service the requirements ofnew industrial developments.

The capacity of the current potable water supply (Millstream borefield and Harding Dam) isinsufficient to meet the requirements of new industries, including the Syntroleum gas to liquidsproject (HLA - Envirosciences Pty Limited (1999a). This proposal provides an alternativesource of high quality process water that meets Syntroleum’s requirements (6.5 ML/day), aswell as providing up to 62 ML/day of seawater for use by future projects. The desalination plantis to be constructed on the Syntroleum site, utilising waste process heat from the Syntroleumplant.

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The general arrangement of the desalination plant is shown in Figure 3. The proposal allows forthe extraction of up to 100 ML/day of seawater from King Bay and the return of a brine streamat a maximum rate of 77 ML/day.

The key components of the proposal are:

• Seawater intake structure, including pump station, onshore screening and electrolyticchlorination;

• Thermo Compression Distillation Plant (6.5 ML/day capacity);

• Cooling tower, water storage facilities and brine pump at the Syntroleum site;

• Seawater supply pipeline to the Syntroleum site (4.6 km);

• Brine discharge pipeline to King Bay (4.6 km); and

• Brine outfall and diffusers.

The main characteristics of the proposal are summarised in Table 1 below.

Table 1. Key Project Characteristics

Element DescriptionProject Purpose To provide high quality water to the Syntroleum project and seawater

for cooling purposes to other proposed industries on the BurrupPeninsula.

Project Life 25 + years.Major ProjectComponents

1. Seawater intake pump system.2. Nominal 6.5 megalitres/day thermal desalination plant.3. Brine cooling tower and water storage facilities.4. Seawater supply pipeline (approximately 4.6 km long).5. Brine discharge pipeline (approximately 4.6 km long).6. Brine outfall and diffusers.

Project Location Seawater intake pump system – within the Mermaid Marine harbourdevelopment.Desalination plant and cooling tower – within the Syntroleum site,King Bay-Hearson Cove Industrial Area.Pipelines – within easements on the eastern side of Burrup Road,northern side of King Bay Road and western side of the MermaidMarine access road and property.Brine outfall and diffuser – extending approximately 500m from theMermaid Marine groyne to a point midway between the MermaidMarine and Woodside shipping channels at 2.5m Chart Datum.

Plant Operation Continuous – up to 24 hours per day, 365 days per year.Plant Storage Capacities Approximately 2 megalitres (1.5 hours) seawater storage.

Approximately 4 megalitres (15 hours) distilled water storage.Inputs: - Seawater Initially – approximately 18 megalitres/day (winter) to approximately

38 megalitres/day (summer).Finally - up to 100 megalitres/day.

- Power Supply Approximately 1MW to 1.5MW, supplied from Syntroleum.Discharges: - Brine Initially - up to 38 megalitres/day at 52,500 milligrams/litre total

dissolved solids. Typically at 2oC above ambient seawatertemperature.Finally - up to 77 megalitres/day at 55,500 milligrams/litre totaldissolved solids. Typically at 2oC above ambient seawatertemperature.

- Antiscalant Approximately 100 kilograms/day

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Element Description - Biocide Normally, nil; decomposed by addition of sodium metabisulphite. - Sulphamic Acid Nil to discharge.Noise: - Construction: Less than 30 dB(A) at the nearest permanent residence (Dampier) - Operation: Seawater intake system: Less than 70 dB(A) at 1m from pump well.

Desalination plant: Less than 30 dB(A) at the nearest permanentresidence (Dampier).

Construction Period Approximately 15 months.Construction Workforce Peak 50 persons.Operational Workforce Estimated 6 persons.

3. ConsultationThe proponent has consulted extensively with stakeholders including government agencies,commercial and community organisations and the local community throughout the project.

The principal stakeholders and community groups identified are shown in Table 2.

Table 2 Identified Stakeholders

Government and CommercialOrganisations

Community Groups

Dampier Port Authority Dampier Archipelago PreservationAssociation

Department of Conservation and LandManagement

Dampier Archipelago ResidentialDwellers Association

Department of Environmental Protection Dampier Skindiving Club

Department of Resource Development Friends of the Burrup

Environmental Protection Authority Hampton Harbour Boat and Sailing Club

Hamersley Iron Associates * Karratha Dive School

Mermaid Marine Pty Ltd * King Bay Game Fishing Club

Shire of Roebourne Naval Reserve Cadets

Water and Rivers Commission Nickol Bay Naturalists (Inc)

Woodside Energy Limited *

* Organisations were directly briefed on the project.Consultation with stakeholders has occurred through meetings, newspaper briefings, radio,internet and press releases. Letters were also sent to identified stakeholders includingcommunity groups, outlining the project and inviting comments on the proposal. An initialround of consultation meetings were held in Karratha during 24 - 25 January 2001.

Although there was general support for the proposal in relation to the perceived benefits ofdesalination, a number of concerns were raised by various stakeholders. The issues raised bythe stakeholders are recorded in the proponent’s EPS document (Table 10.2). The main issuesinclude:

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• Need for further hydrodynamic modelling to determine the effects of pumping onturbidity;

• More information needed on the distillation process;• Concerns regarding weed control management;• Impact of brine on local coral communities near outlet;• Need to address Aboriginal heritage requirements; and• The future use of the pipeline in relation to the wastewater disposal via the pipeline.

A second round of consultation meetings was held with the stakeholders during 8 - 9 March2001 to feed back requested information and gather additional comments. The stakeholdercomments and proponent responses are summarised in Table 10.3 of the proponent’sdocument. The proponent has addressed the issues raised by the stakeholders within the EPSdocument, including:

• Conduct further hydrodynamic modelling (far-field modelling) to predict impacts from thebrine discharge on marine flora and fauna;

• A commitment to a weed management plan;• A commitment to a heritage management plan; and• Confirmation that approval is sought for brine and cooling water disposal only.

The specific details of the distillation process were not included in the EPS due to itscomplexity, but the process was discussed at length and in detail with the relevant stakeholders.

The stakeholder comments during the second round of consultation indicated generalwidespread support for the project. The proponent will continue to keep stakeholders informedof the progress of the project development and provide written responses to concerns raised byorganisations and individuals. In addition, DEP concerns in relation to risk managementcompatibility with the Syntroleum plant have been addressed by the proponent committing tomake the desalination plant compliant with Syntroleum’s safety and hazard managementrequirements.

4. Relevant environmental factorsThe summary of all of the environmental factors and their management is outlined in Table A ofthe EPS (pages 6-13, Burrup Peninsula Desalinated Water and Seawater Supplies Project,Burns and Roe Worley Pty Ltd, 2001).

In the EPA’s opinion the following are the environmental factors relevant to the proposal:

a) Terrestrial flora – vegetation clearing and weed invasion from construction activities;

b) Marine flora and fauna – subsea trench construction and brine discharge; and

c) Visual amenity – visual impact of seawater intake and brine discharge pipelines.

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Terrestrial flora

The EPA’s environmental objectives for this factor are to:

1. Protect Declared Rare and Priority Flora consistent with the provisions of the WildlifeConservation Act, 1950 and the Commonwealth’s Endangered Species Protection Act1992; and

2. Maintain the abundance, species diversity, geographical distribution and productivity ofvegetation communities.

The desalination plant and associated equipment will be located within the confines ofSyntroleum’s natural gas to synthetic hydrocarbons plant. The land required for the desalinationplant is relatively small (0.6 hectares) and will be cleared prior to construction of theSyntroleum plant. The environmental impacts from clearing have been reported by the EPA inthe assessment of the Syntroleum proposal (EPA, 2000) and its consolidated document ofchanges, dated 26 April 2001.

The construction of the intake and discharge pipelines will disturb a 20m corridor of vegetationalong the length of the pipeline route (4.6 km). The selected route for the pipelines has beenbased on the use of road reserves, existing easements and service corridors proposed by theDepartment of Resources Development. A total of about 13 hectares of vegetation will becleared or trampled during construction. An area of only about 3 hectares of undisturbedgrassland will be affected, approximately 10 hectares having been cleared previously. Thesection of pipeline in the undisturbed area will be located above ground, minimising impacts onthe vegetation.

The construction of the pipeline infrastructure may affect vegetation communities and DeclaredRare and Priority Flora as a result of the following:

• Flora will be removed from the pipeline corridor;

• Priority species will be disturbed;

• Sensitive habitats and significant vegetation communities may be removed; and

• Exotic weeds may be introduced and spread.

No Declared Rare Plants as listed for Western Australia under the Wildlife Conservation Act,1950 or plants listed under the Commonwealth’s Endangered Species Protection Act 1992 werefound in the surveyed area. The priority flora identified along the proposed route included:

• Terminalia supranitifolia (Priority 1); and

• Eriachne tenuiculmis (Priority 3)

The proponent has committed to conducting a more detailed vegetation survey in the appropriateseason, prior to construction. Any identified rare and priority species along the proposed routewill be tagged with a view to avoiding disturbance where practicable. Where impacts uponpriority flora cannot be avoided, the proponent will relocate or replace all of the specimensaffected.

Weed spread is highly likely as a result of construction activities unless adequate controls are inplace. A total of five weeds (Aerva javanica, Cenchrus ciliaris, Stylosanthes hamata, Passiflorafoetida and Pennisetum setaceum) were identified during the vegetation survey. A further twospecies (Rumex vesciarius and Euphorbia hirsute) have previously been identified along theproposed pipeline route. The proponent will develop and enforce a weed management planapproved by the Department of Conservation and Land Management (CALM). Included in theplan will be the removal of all weed species along the pipeline route and the establishment of avehicle wash down facility.

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Construction and laydown areas will be rehabilitated and monitored over a 15 year period.However, complete rehabilitation in which species richness and cover is indistinguishable fromundisturbed countryside is not expected.

The EPA concludes that based on the management plans and commitments made by theproponent, the proposal would not compromise the EPA’s environmental objectives for thisfactor.

Marine flora and fauna

The proposal has the potential to impact on the marine flora and fauna during:

• Construction of the proposed seawater intake and brine outfall facilities; and

• Operation of the seawater supply and brine outlet systems.

The EPA’s environmental objective for this factor is to maintain the ecological function,abundance, species diversity and geographic distribution of marine flora (seagrass and macro-algae) and marine fauna.

Construction of inlet and outlet facilities

A benthic mapping survey (IRC Environment, February 2001) was conducted to documentcorals and benthic macrophytes in the vicinity of the seawater inlet and brine outlet facilities.The seabed was found to be mainly sand, mud and coarse shell. Marine habitats and biota in thearea was relatively sparse and typical of habitats widely distributed in the Dampier region.Burrowing worms and crustaceans were found to be the predominant fauna. Informationavailable to date indicates that no coral communities or extensive seagrass beds exist within theconfines of King Bay. None of the marine biota observed in the area are listed as especiallyprotected, endangered, vulnerable or threatened under the Commonwealth EnvironmentalProtection and Biodiversity Conservation Act or the Western Australian Wildlife Protection Act.

The marine flora and fauna in the vicinity of the proposed offshore seawater supply and brinedisposal facilities will be disturbed during the excavation of the 500m subsea trench andsubsequent pipeline installation and stabilisation. The area of disturbance is expected to be about1 hectare (approximately 1%) of the King Bay seabed.

The seawater in King Bay is naturally turbid throughout the year due to the nature of theseabed, the wind and the high tide variation. However, construction activities will lead to ashort term (several weeks) increase in turbidity. It is considered that this increase in turbiditywill be minimal when compared with the recent large scale dredging operation within the bay.The proponent will employ best available dredging construction methods and techniques. Adredging and spoil disposal plan will be developed that includes the monitoring of dissolvedoxygen and turbidity and activities will be stopped if values exceed acceptable levels at theperiphery of an accepted disturbance zone. Sub-sea excavation will be avoided during theperiods when corals are spawning. Sediment sampling indicates low levels of heavy metal andthat the sediment has a low potential for re-suspension (Astron Engineering, 1998). Anyredistribution of sediments in King Bay as a result of construction activities is therefore notexpected to make a significant difference to the environment.

As only local infauna (animals inhabiting the sediments) will be affected, the EPA considers theimpacts due to construction of the pipeline will not be significant.

Operation of seawater supply and brine discharge system

The proponent will operate and manage the desalination plant and seawater supply and brinedischarge system. The brine discharge stream (77 ML/day) will essentially be seawater with anelevated salinity (approximately 38% above ambient) and temperature (typically 2 0C aboveambient). It will also contain an anti-scalant (sodium salt of a polycarboxylic acid) and lowconcentrations of biocides (typically chlorine) and byproducts. Although a cleaning agent(sulphamic acid) will occasionally be used to remove scale from the desalination system, it willbe collected and disposed of appropriately.

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A hydrodynamic assessment (Worley, March 2001) was undertaken to predict theenvironmental impacts associated with the ongoing withdrawal of seawater from, and therelease of the brine discharge to the natural environment. Near-field modelling (CORMIXv.3.2) of the saline plume (55,000 mg/L) predicted that the ANZECC environmental qualitycriteria (EQC) (ANZECC, October 2000) for salinity (<5 % variation) would be met, apart fromwithin a 40m mixing zone at the outfall. Near-field modelling for thermal dispersion was basedon a high, worst case discharge temperature of 50 C above ambient seawater temperature. Themodel predicted that within 7m and110m of the outfall the temperature elevation would be lessthan 20 C and 0.250 C above ambient, respectively.

Both the DEP and CALM have reviewed the hydrodynamic modelling and found themethodology used and the predicted impacts acceptable. However, on the basis of availableinformation, the corals in the region are near the threshold of their thermal tolerance during thesummer months. The EPA considers that the thermal load from this project should beminimised as low as reasonably practicable, in addition to meeting acceptable environmentalquality criteria. The proponent has made the following commitments to ensure impacts fromthermal pollution are negligible:

• A cooling tower will be installed that is designed to cool the brine to within 30 C of thewet bulb temperature. (A comparison of seawater temperatures with meteorological dataindicate that on average the brine discharge is expected to be cooled to within 20 C of theambient seawater temperature);

• The daily variation between seawater inlet and brine outfall temperatures will bemonitored and recorded; and

• Operations will be manage to ensure that the brine discharge (end of pipe) temperature:

o is less than 20 C above ambient seawater temperature for 80% of the time; and

o does not exceed 50 C above ambient seawater temperature.

unless otherwise agreed by the DEP.

The potential impact of the brine discharge on flora and fauna in King Bay and Mermaid Soundwas predicted using a far field 3 dimensional model called Environmental Fluid Dynamics Code(EFDC). The far field effects of salinity, temperature and any accumulation of othercontaminants were determined. The model predicted that the EQC salinity guidelines would notbe exceeded outside the near field mixing zone (40m), although the dense plume will causesome stratification to occur in the dredged basins and channels.

The seawater temperature in the vicinity of the proposed outfall was found to vary due to naturalcauses by as much as 20 C over a tidal cycle and by up to 50 C in a month. The temperaturevariation is caused by the large area of shallow water in King Bay and the large tides in theregion. Far field modelling predicted the temperature increase to be less than 0.10 C aboveambient within a few hundred metres of the discharge. The EPA considers the predictedtemperature increase to be acceptable, given that the nearest coral communities areapproximately 500m away. The proponent has committed to a coral management plan whichwould include appropriate monitoring programs to ensure no adverse impacts to the local coralcommunities. The data can also be used to verify the dispersion modelling results.

Low levels of heavy metals may be present in the brine discharge from corrosion or othersources. However, numerical modelling indicates that King Bay is well flushed and noaccumulation of contaminants is expected. In addition, the proponent has committed toundertaking a program of sampling the seawater and sediments in the vicinity of the outfall toconfirm that the level of heavy metals are within established limits.

Acute toxicity tests indicate that the antiscalant will not be harmful to the marine biota at theanticipated dose rate (typically less than 2 mg/L in the brine discharge). The proponent hascommitted to conducting chronic toxicity tests or obtaining chronic toxicity data prior tocommissioning. The residual biocide (chlorine) in the brine discharge will be continuouslymonitored and dechlorinated by the controlled addition of sodium metabisulphite to produce

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ions naturally present in seawater. A second on-line chlorine monitoring system will be installedto confirm that the chlorine concentration has been reduced to below detectable limits(< 0.1 mg/L).

Continuous on-line monitoring of brine turbidity will be used to determine long term trends andestablish whether additional controls are required. As the seawater in the region is naturallyturbid and subject to disturbance from vessel movements, any minor increase in turbidity due tothe brine discharge is not expected to affect the marine flora and fauna.

The proponent has committed to undertaking a brine, seawater, sediment and biota monitoringprogram. The program will establish baseline data, validate modelling results and determinelong term effects on the biota. Heavy metals and process chemicals will be monitored. Athorough screening analysis will be conducted periodically on the brine to verify that it does notcontain any environmentally damaging constituents. If monitoring identifies any unacceptableimpacts, modifications will be made to mitigate adverse effects.

The water velocity at the screen surface of the seawater discharge pumps will not exceed 0.15m/s to reduce scouring of the seabed and prevent entrapment of marine fauna against the screen.

The EPA concludes that based on the results of the near and far field modelling and thecommitments made by the proponent, the seawater supply and brine discharge can be managedto meet the EPA’s objective for this factor.

Visual Amenity

The Burrup Peninsula has outstanding scenic values and is therefore a popular tourist andrecreational destination. However, the area is also strategically placed for industrialdevelopment and a number of large industrial developments are being proposed within areasthat have been zoned industrial. The EPA accepts that the visual amenity of the region will bereduced as a result of industrial development. The EPA’s objective is to ensure that theproponent considers aesthetic values, and that measures are put in place to reduce the visualimpact of the developments on the surrounding countryside as low as reasonably practicable.

The project has the potential to reduce the visual amenity of the Burrup as it includes theinstallation of large diameter (0.45m to 0.9m) seawater supply and brine discharge pipelines.For approximately half of the route the pipelines will be buried, however they will be locatedabove ground on the hard, rocky areas, where burial is considered to be impractical. Theexposed section of the pipelines will extend for approximately 2 kms following alongsideBurrup and King Bay Roads. The proponent has committed to reducing the visual impact fromBurrup Road by:

1. Using excess rock and soil to screen the pipelines; and

2. Painting the pipelines in a colour that blends in with the environment.

Access will be required to sections of the pipelines, but only a four wheel drive track isenvisaged. The proponent will not construct a vehicle access road without DEP approval.

The pipelines alongside King Bay Road will be highly visible, but given the existingdevelopment in King Bay and the fact that, this area is of lesser importance from a tourism andrecreational perspective, the EPA considers that the visual impact is acceptable.

The main plant includes a thermal desalination unit, seawater and desalinated water storagetanks and a cooling tower which are to be located on the Syntroleum site, next to major processitems for the synthetic hydrocarbons plant. The visual impact of these additional items isconsidered to be insignificant in the context of the Syntroleum plant. Construction and laydownareas will be rehabilitated to ensure there is no long-term reduction in visual amenity as a resultof clearing activities.

The EPA considers that the visual impact of the project will be consistent with the developmentthat is being considered for the region. The proponent has made commitments that will reducevisual impacts from Burrup Road. The EPA notes that the desalination plant will not be visible

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from the popular recreational beach at Hearson Cove. It concludes that the proposal can bemanaged to meet the EPA’s objective for this factor.

5. Conclusions

Section 44 of the Environmental Protection Act 1986 requires the EPA to report to the Ministerfor the Environment on the environmental factors relevant to the proposal and on the conditionsand procedures to which the proposal should be subject, if implemented. In addition, the EPAmay make recommendations as it sees fit.

The EPA concludes that the factor of terrestrial flora can be managed to meet the EPA’sobjective to:

1. Protect Declared Rare and Priority Flora consistent with the provisions of the WildlifeConservation Act, 1950 and the Commonwealth’s Endangered Species Protection Act1992; and

2. Maintain the abundance, species diversity, geographical distribution and productivity ofvegetation communities.

Only 3 hectares of undisturbed grassland will be affected and the proponent has madecommitments that are expected to reduce impacts on the vegetation, preserve priority flora andprevent the spread of weeds during construction.

The EPA concludes that the factor of marine flora and fauna can be managed to meet the EPA’sobjective to maintain the ecological function, abundance, species diversity and geographicdistribution of marine flora (seagrass and macro-algae) and marine fauna. Modelling indicatesthat the EQC guidelines will be met apart from within a 40m mixing zone at the outfall. Thepredicted increase in seawater temperature near the outfall is considered to be acceptable.Impacts will be limited to local infauna, while nearby coral reef systems are not predicted to beaffected. The proponent will undertake a brine, seawater, sediment and biota monitoringprogram to establish baseline data and test for any long term effects on the biota.

The EPA concludes that the factor of visual amenity can be managed to meet the EPA’sobjective of ensuring that the visual amenity of the area adjacent to the project is not undulyaffected by the proposal.

6. Recommendations

The EPA considers that the proponent has demonstrated, in its EPS document, that the proposalcan be managed in an environmentally acceptable manner and that concerns raised instakeholder consultation have been taken into account. The EPA provides the followingrecommendations to the Minister for the Environment:

1. That the Minister notes that the proposal being assessed is for the Desalination andSeawater Supplies Project, Burrup Peninsula.

2. That the Minister notes that this report follows a decision by the EPA to set a level ofassessment as Proponent-initiated Environmental Protection Statement because:

• The potential impacts can be managed through enforceable conditions, so thatimpacts are not significant, thus more comprehensive assessment under Part IV ofthe Environmental Protection Act 1986 is not warranted.

• The proponent’s commitments in relation to the environmental factors identifiedneed to be made legally binding through the Environmental Conditions set inaccordance with Part IV of the Environmental Protection Act 1986.

3. That the Minister considers the report on the relevant environmental factors as set out inSection 4.

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4. That the Minister notes that the EPA has concluded that it is unlikely that the EPA’sobjectives would be compromised, provided there is satisfactory implementation by theproponent of the recommended conditions and proponent commitments as set out inAppendix 2, including the provision for implementation of an environmental managementsystem.

5. That the Minister imposes the conditions and procedures recommended in Appendix 2 ofthis report.

Appendix 1References

ANZECC, October 2000. Australian and New Zealand Guidelines for Fresh and Marine WaterQuality – National Water Quality Management Strategy. Australian and New ZealandEnvironment and Conservation Council Agriculture and Resource Management Council ofAustralia.

Astron Engineering, 1998. Investigative Sampling at King Bay.

Burns and Roe Worley, April 2001. Burrup Peninsula Desalinated Water and SeawaterSupplies Project Environmental Protection Statement.

EPA (2000) Proposed Gas to Synthetic Hydrocarbons Plant, Burrup Peninsula, WesternAustralia. Environmental Protection Authority Bulletin 985, July 2000.

HLA - Envirosciences Pty Limited (1999a). Syntroleum Proposed Gas to SyntheticHydrocarbons Plant, Burrup Peninsula, Western Australia. Consultative EnvironmentalReview.

IRC Environment, February 2001. Water Corporation Dampier Marine Environmental Survey.

Worley, March 2001. Burrup Peninsula Desalination Plant Hydrodynamic Assessment.

Appendix 2Recommended Environmental Conditions

and Proponent’s Consolidated Commitments

Schedule 2Proponent�s Consolidated Commitments � Desalinated and Seawater Supplies Project, Burrup Peninsula (Ass. No. 1378)

No Topic Action Objective Timing Advice1 Terrestrial Flora 1) Prepare a weed management plan.

2) Implement the weed management plan.

To prevent the introduction ofnew weeds.

To control existing weeds.

Pre-construction

Construction

CALMAgwest (fornoxious weeds)

2 Terrestrial Flora Conduct a detailed vegetation survey along thepipeline route, in the appropriate season.

To identify and protectsensitive flora.

Pre-construction CALM

3 Terrestrial Flora 1) Prepare a flora and vegetation plan:

• to quantify area of vegetation to bedisturbed and the values that would belost.

2) Implement the flora and vegetation plan.

To protect significant, rare andendangered flora.

To protect significantvegetation assemblages.

Pre-construction

Construction

CALM

4 Terrestrial Flora 1) Prepare a rehabilitation management planfor the construction and laydown areas:

• to monitor vegetation assemblages.

2) Implement the rehabilitation managementplan.

To measure and report onrehabilitation success.

Construction

Annually for 5 years,then biannually for afurther 10 years.

CALM

5 Terrestrial Fauna Construct suitable fauna passages beneath theabove ground sections of the pipelines.

To protect significant faunahabitats and their access.

To protect rare and endangeredfauna.

Construction CALM

6 Marine Flora andFauna

1) Prepare a dredging and spoil disposal planthat incorporates the best practicallyavailable dredging construction methodsand techniques:

• to minimise generation of turbidity;

• to minimise redistribution ofcontaminants;

• to minimise visual impacts; and

• to ensure seawater oxygen levels arenot depleted.

To protect benthic flora andfauna.

To minimise the extent ofdisturbance of benthic floraand fauna.

Pre-construction

2) Implement the dredging and spoil disposalplan.

Construction


1) Prepare a brine discharge quality plan tomonitor and control emissions:

• Continuous on-line monitoring shallinclude flow rate, temperature,conductivity, oxidation-reductionpotential and turbidity.

• Appropriate additional monitoring shallbe conducted to control discharge levelsof any process additives and otherenvironmental contaminants (such asheavy metals) as required by the DEP.

• Brine discharge temperature to be lessthan 20 C* above the inlet seawatertemperature for 80% of the time and notexceeding a maximum limit of 50 Cabove, unless otherwise agreed with theDEP.

• The concentration of oxidising biocidein the brine discharge to be less than 0.1mg/L.

• The concentration of antiscalant in thebrine discharge to be less than 2 mg/L,unless otherwise agreed with the DEP.

• The proponent will design and operatethe plant to minimize thermal loads tothe marine environment as low asreasonable practicable.

2) Implement the brine discharge quality plan.

3) If monitoring identifies unacceptableimpacts, modifications will be made tomitigate adverse effects.

To protect sessile flora andfauna.

Pre-commissioning

Operation

On-going


1) Conduct a research program to determinethe chronic toxicity of antiscalant onappropriate marine biota.

2) Implement the findings.


Pre-commissioning

Operation


Chemical additives described in the EPS will notbe changed without prior approval.


On-going


1) Prepare a plan to monitor contaminants inthe seawater, sediment and biota.

2) Implement the plan.


To establish baseline data forthe concentrations of heavymetals, process chemicals andother relevant contaminants.

To identify long term effectson biota.


Pre-commissioning

Operation

On-going


1) Prepare a water quality monitoring plan thatincludes the monitoring of caged �sentinel�organisms around the brine outfall.

2) Implement the water quality monitoringplan.


To establish baseline data.

To identify effects on biota.

To protect marine flora andfauna.

To protect mangrovecommunities.

Pre-construction

For a minimum of 18months aftercommissioning.

On-going


1) Prepare a coral management plan to ensureno adverse impacts on coral communitiesparticularly the nearest corals to thedischarge diffuser. The plan will includeintensive monitoring of temperature at theintake and outfall, at appropriate locationsbetween the outfall and the nearest coralcommunity and at appropriate referencelocations, over the months of December toApril, following commissioning of theplant.

To protect local coralcommunities.

To verify the dispersionmodelling results.

To interpret the results of anycoral monitoring program.

Pre-commissioning

Operation

CALM


3) If monitoring identifies unacceptableimpacts from the project, modifications willbe made to mitigate adverse effects.Unacceptability of impacts will be inconsultation with the DEP.

On-going

13 Visual Amenity 1) Prepare a visual amenity plan that includes:

• Mounding of excess soil and rock toform a visual screen where practicable;

• Painting pipelines in colours that blendwith the environment; and

• No construction of a pipelinemaintenance access road, unlessotherwise agreed with the DEP.


To provide a visual screen ofthe pipelines from BurrupRoad.

To prevent unacceptable visualimpacts.

Pre-construction

Construction

14 AboriginalHeritage

1) Prepare an Aboriginal heritage plan to:

• identify all sites of culturalsignificance;

• provide guidelines for avoidance of andbehaviour around sites; and

• provide guidelines if artifacts are found.

2) Implement the Aboriginal heritage plan.

To minimise disturbance tosites of cultural significance.

Pre-construction

Construction

15 Risk Plant design and operation to be compliant withSyntroleum�s Safely Report and Emergency Plan(as required by the Worksafe National Standardfor the Control of Major Hazard Facilities).

To ensure safe operation inproximity to a major hazardfacility.

Design compliance -pre-construction.Operation compliance �prior to operation ofSyntroleum plant.

DME

*The difference between the 24 hour average seawater intake temperature and the brine discharge temperature.Agwest = Agriculture Western AustraliaCALM = Conservation and Land ManagementDEP = Department of Environmental ProtectionDME = Department of Minerals and Energy

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